package Sort.sort2020;

/**
 * 希尔排序
 *
 * @author leiwenkang
 * @date 2020/3/29
 */
public class ShellSort {
    public static void main(String[] args) {
        int[] array = {3, 8, 4, 6, 7, 2, 5, 9, 1};
        shelltSort(array);
        for (int i = 0; i < array.length; i++) {
            System.out.print(array[i]);
            System.out.print(" ");
        }
    }

    public static void shelltSort(int[] array) {
        if (array == null || array.length == 0) {
            return;
        }

        int increment = array.length;
        while (increment > 1) {
            increment = increment / 3 + 1;
            for (int i = increment; i < array.length; i += increment) {
                if (array[i] < array[i - increment]) {
                    //找到插入的位置
                    int val = array[i];
                    int j;
                    for (j = i - increment; j >= 0 && array[j] > val; j -= increment) {
                        array[j + increment] = array[j];
                    }
                    array[j + increment] = val;
                }
            }
        }
    }
}
